Development of the hypothalamic-hypophysial-gonadotrophic activities in fetal rats.
Pituitary responsiveness to LHRH and anti-LHRH serum was investigated in fetal rats aged 18.5-22.5 days. Synthetic LHRH injection in utero into fetuses brought about a remarkable depletion of pituitary-LH with a corresponding increase of serum-LH on day 18.5. On the contrary, anit-LHRH serum administration to day-20.5 fetuses caused a significant augmentation of pituitary-LH 1 day later. These data indicate that LH-gonadotrophs respond to LHRH even on day 18.5, and that endogenous LHRH begins to affect LH gonadotrophs on day 20.5.
D000818:Animals; D005260:Female; D005640:Follicle Stimulating Hormone / Q000378:metabolism; D005865:Gestational Age; D007987:Gonadotropin-Releasing Hormone / Q000494:pharmacology; D007030:Hypothalamo-Hypophyseal System / Q000187:drug effects / Q000196:embryology*; D007986:Luteinizing Hormone / Q000378:metabolism; D008297:Male; D010053:Ovary / Q000196:embryology*; D011247:Pregnancy; D051381:Rats; D011919:Rats, Inbred Strains; D013737:Testis / Q000196:embryology*
D007987:Gonadotropin-Releasing Hormone; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone